Plumbing in the Home/plumbing


QUESTION: Kitchen sink, water turned off at valves under sink. Water keeps coming up the sink, and filling sink. Drain is clogged waiting to hook up to sewer, not using any water in kitchen. Valves turned off, clean water still keep filling sink.
What the heck is going on?


ANSWER: Sounds like water is getting into the drainage system somewhere and backing up into the kitchen sink.  That's odd since it is not the lowest fixture drain in the system. That would be the tub drain and that's where a backup usually shows up first. Not sure where else water could be coming from.

The water supply valves under the sink do not always work in any case. Old valves often do not shut off completely.

I'm a bit unsure about the comment "waiting to hook up to the sewer".  Are you on a septic system and waiting for a connection to the city sewer system?

---------- FOLLOW-UP ----------

QUESTION: Yes on septic now, the small kitchen tank is full.
However the water coming up is clean, the house was built in the 50's. The water is coming from somewhere, must be the turn off valves are failing? What else could it be?

Hi Charlene,
This type of problem is very difficult to diagnose without being there to investigate.

The waste piping is all connected together and water use in one location can back up in another if there is no outlet for that location. Until you actually get the drain working at the kitchen sink, this problem is likely to continue.
if there is a clean out on the drain piping for that sink, (there should be)opening it on the outside will drain the sink temporarily until the problem can be resolved.
Good Luck,

Plumbing in the Home

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Dana Bostick


Pretty much any residential plumbing questions. For "item specific" details such as a specific model of fixture, I will need to research and there may not be any useful information available. Note: I live and work in Southern California. We do not, as a rule, use hot water or steam heating systems, oil fired boilers or private water wells so my knowledge in those areas is pretty limited. There are others here on AllExerts that can probably answer those questions better.


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